.TH "std::shared_ptr< _Tp >" 3 "libstdc++" \" -*- nroff -*-
.ad l
.nh
.SH NAME
std::shared_ptr< _Tp > \- A smart pointer with reference-counted copy semantics\&.  

.SH SYNOPSIS
.br
.PP
.PP
\fR#include <memory>\fP
.PP
Inherits std::__shared_ptr< _Tp, _Lp >\&.
.SS "Public Types"

.in +1c
.ti -1c
.RI "\fBusing\fP \fBelement_type\fP"
.br
.RI "The type pointed to by the stored pointer, remove_extent_t<_Tp> "
.ti -1c
.RI "\fBusing\fP \fBweak_type\fP"
.br
.RI "The corresponding weak_ptr type for this shared_ptr\&. "
.in -1c
.SS "Public Member Functions"

.in +1c
.ti -1c
.RI "\fBconstexpr\fP \fBshared_ptr\fP () noexcept"
.br
.RI "Construct an empty shared_ptr\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP , typename  = _Constructible<_Yp*>> \fBshared_ptr\fP (\fB_Yp\fP *__p)"
.br
.RI "Construct a shared_ptr that owns the pointer \fI__p\fP\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP , typename \fB_Deleter\fP , typename  = _Constructible<_Yp*, _Deleter>> \fBshared_ptr\fP (\fB_Yp\fP *__p, \fB_Deleter\fP __d)"
.br
.RI "Construct a shared_ptr that owns the pointer \fI__p\fP and the deleter \fI__d\fP\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP , typename \fB_Deleter\fP , typename _Alloc , typename  = _Constructible<_Yp*, _Deleter, _Alloc>> \fBshared_ptr\fP (\fB_Yp\fP *__p, \fB_Deleter\fP __d, _Alloc __a)"
.br
.RI "Construct a shared_ptr that owns the pointer \fI__p\fP and the deleter \fI__d\fP\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP , typename  = _Constructible<auto_ptr<_Yp>>> \fBshared_ptr\fP (\fBauto_ptr\fP< \fB_Yp\fP > &&__r)"
.br
.ti -1c
.RI "\fBshared_ptr\fP (\fBconst\fP \fBshared_ptr\fP &) noexcept=\fBdefault\fP"
.br
.RI "Copy constructor\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP , typename  = _Constructible<const shared_ptr<_Yp>&>> \fBshared_ptr\fP (\fBconst\fP \fBshared_ptr\fP< \fB_Yp\fP > &__r) noexcept"
.br
.RI "If \fI__r\fP is empty, constructs an empty shared_ptr; otherwise construct a shared_ptr that shares ownership with \fI__r\fP\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP > \fBshared_ptr\fP (\fBconst\fP \fBshared_ptr\fP< \fB_Yp\fP > &__r, \fBelement_type\fP *__p) noexcept"
.br
.RI "Constructs a \fRshared_ptr\fP instance that stores \fR__p\fP and shares ownership with \fR__r\fP\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP , typename  = _Constructible<const weak_ptr<_Yp>&>> \fBshared_ptr\fP (\fBconst\fP \fBweak_ptr\fP< \fB_Yp\fP > &__r)"
.br
.RI "Constructs a shared_ptr that shares ownership with \fI__r\fP and stores a copy of the pointer stored in \fI__r\fP\&. "
.ti -1c
.RI "template<typename \fB_Deleter\fP > \fBshared_ptr\fP (nullptr_t __p, \fB_Deleter\fP __d)"
.br
.RI "Construct a shared_ptr that owns a null pointer and the deleter \fI__d\fP\&. "
.ti -1c
.RI "template<typename \fB_Deleter\fP , typename _Alloc > \fBshared_ptr\fP (nullptr_t __p, \fB_Deleter\fP __d, _Alloc __a)"
.br
.RI "Construct a shared_ptr that owns a null pointer and the deleter \fI__d\fP\&. "
.ti -1c
.RI "\fBconstexpr\fP \fBshared_ptr\fP (nullptr_t) noexcept"
.br
.RI "Construct an empty shared_ptr\&. "
.ti -1c
.RI "\fBshared_ptr\fP (\fBshared_ptr\fP &&__r) noexcept"
.br
.RI "Move-constructs a shared_ptr instance from \fI__r\fP\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP , typename  = _Constructible<shared_ptr<_Yp>>> \fBshared_ptr\fP (\fBshared_ptr\fP< \fB_Yp\fP > &&__r) noexcept"
.br
.RI "Move-constructs a shared_ptr instance from \fI__r\fP\&. "
.ti -1c
.RI "template<typename \fB_Yp\fP > \fBshared_ptr\fP (\fBshared_ptr\fP< \fB_Yp\fP > &&__r, \fBelement_type\fP *__p) noexcept"
.br
.RI "Constructs a \fRshared_ptr\fP instance that stores \fR__p\fP and shares ownership with \fR__r\fP\&. "
.ti -1c
.RI "template<typename \fB_Tp1\fP , typename > \fBshared_ptr\fP (\fBstd::auto_ptr\fP< \fB_Tp1\fP > &&__r)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename \fB_Del\fP , typename  = _Constructible<unique_ptr<_Yp, _Del>>> \fBshared_ptr\fP (\fBunique_ptr\fP< \fB_Yp\fP, \fB_Del\fP > &&__r)"
.br
.ti -1c
.RI "\fBelement_type\fP * \fBget\fP () \fBconst\fP noexcept"
.br
.RI "Return the stored pointer\&. "
.ti -1c
.RI "\fBoperator bool\fP () \fBconst\fP noexcept"
.br
.RI "Return true if the stored pointer is not null\&. "
.ti -1c
.RI "\fBelement_type\fP & \fBoperator*\fP () \fBconst\fP noexcept"
.br
.ti -1c
.RI "\fBelement_type\fP * \fBoperator\->\fP () \fBconst\fP noexcept"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > _Assignable< \fBauto_ptr\fP< \fB_Yp\fP > > \fBoperator=\fP (\fBauto_ptr\fP< \fB_Yp\fP > &&__r)"
.br
.ti -1c
.RI "\fBshared_ptr\fP & \fBoperator=\fP (\fBconst\fP \fBshared_ptr\fP &) noexcept=\fBdefault\fP"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > _Assignable< \fBconst\fP \fBshared_ptr\fP< \fB_Yp\fP > & > \fBoperator=\fP (\fBconst\fP \fBshared_ptr\fP< \fB_Yp\fP > &__r) noexcept"
.br
.ti -1c
.RI "\fBshared_ptr\fP & \fBoperator=\fP (\fBshared_ptr\fP &&__r) noexcept"
.br
.ti -1c
.RI "template<\fBclass\fP \fB_Yp\fP > _Assignable< \fBshared_ptr\fP< \fB_Yp\fP > > \fBoperator=\fP (\fBshared_ptr\fP< \fB_Yp\fP > &&__r) noexcept"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename \fB_Del\fP > _Assignable< \fBunique_ptr\fP< \fB_Yp\fP, \fB_Del\fP > > \fBoperator=\fP (\fBunique_ptr\fP< \fB_Yp\fP, \fB_Del\fP > &&__r)"
.br
.ti -1c
.RI "\fBvoid\fP \fBreset\fP () noexcept"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > _SafeConv< \fB_Yp\fP > \fBreset\fP (\fB_Yp\fP *__p)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename \fB_Deleter\fP > _SafeConv< \fB_Yp\fP > \fBreset\fP (\fB_Yp\fP *__p, \fB_Deleter\fP __d)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename \fB_Deleter\fP , typename _Alloc > _SafeConv< \fB_Yp\fP > \fBreset\fP (\fB_Yp\fP *__p, \fB_Deleter\fP __d, _Alloc __a)"
.br
.ti -1c
.RI "\fBvoid\fP \fBswap\fP (__shared_ptr< _Tp, \fB_Lp\fP > &__other) noexcept"
.br
.RI "Exchange both the owned pointer and the stored pointer\&. "
.ti -1c
.RI "bool \fBunique\fP () \fBconst\fP noexcept"
.br
.RI "Return true if use_count() == 1\&. "
.ti -1c
.RI "long \fBuse_count\fP () \fBconst\fP noexcept"
.br
.RI "If *this owns a pointer, return the number of owners, otherwise zero\&. "
.in -1c
.PP
.RI "\fB\fP"
.br

.in +1c
.in +1c
.ti -1c
.RI "template<typename \fB_Tp1\fP > bool \fBowner_before\fP (__shared_ptr< \fB_Tp1\fP, \fB_Lp\fP > \fBconst\fP &\fB__rhs\fP) \fBconst\fP noexcept"
.br
.RI "Define an ordering based on ownership\&. "
.ti -1c
.RI "template<typename \fB_Tp1\fP > bool \fBowner_before\fP (__weak_ptr< \fB_Tp1\fP, \fB_Lp\fP > \fBconst\fP &\fB__rhs\fP) \fBconst\fP noexcept"
.br
.RI "Define an ordering based on ownership\&. "
.in -1c
.in -1c
.SS "Friends"

.in +1c
.ti -1c
.RI "template<typename \fB_Yp\fP , typename _Alloc > \fBshared_ptr\fP< \fB_BoundedArray\fP< \fB_Yp\fP > > \fBallocate_shared\fP (\fBconst\fP _Alloc &)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename _Alloc , typename\&.\&.\&. _Args> \fBshared_ptr\fP< \fB_NonArray\fP< \fB_Yp\fP > > \fBallocate_shared\fP (\fBconst\fP _Alloc &, \fB_Args\fP &&\&.\&.\&.)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename _Alloc > \fBshared_ptr\fP< \fB_BoundedArray\fP< \fB_Yp\fP > > \fBallocate_shared\fP (\fBconst\fP _Alloc &, \fBconst\fP \fBremove_extent_t\fP< \fB_Yp\fP > &)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename _Alloc > \fBshared_ptr\fP< \fB_UnboundedArray\fP< \fB_Yp\fP > > \fBallocate_shared\fP (\fBconst\fP _Alloc &, size_t)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename _Alloc > \fBshared_ptr\fP< \fB_UnboundedArray\fP< \fB_Yp\fP > > \fBallocate_shared\fP (\fBconst\fP _Alloc &, size_t, \fBconst\fP \fBremove_extent_t\fP< \fB_Yp\fP > &)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename _Alloc > \fBshared_ptr\fP< \fB_NotUnboundedArray\fP< \fB_Yp\fP > > \fBallocate_shared_for_overwrite\fP (\fBconst\fP _Alloc &)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename _Alloc > \fBshared_ptr\fP< \fB_UnboundedArray\fP< \fB_Yp\fP > > \fBallocate_shared_for_overwrite\fP (\fBconst\fP _Alloc &, size_t)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > \fBshared_ptr\fP< \fB_BoundedArray\fP< \fB_Yp\fP > > \fBmake_shared\fP ()"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP , typename\&.\&.\&. _Args> \fBshared_ptr\fP< \fB_NonArray\fP< \fB_Yp\fP > > \fBmake_shared\fP (\fB_Args\fP &&\&.\&.\&.)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > \fBshared_ptr\fP< \fB_BoundedArray\fP< \fB_Yp\fP > > \fBmake_shared\fP (\fBconst\fP \fBremove_extent_t\fP< \fB_Yp\fP > &)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > \fBshared_ptr\fP< \fB_UnboundedArray\fP< \fB_Yp\fP > > \fBmake_shared\fP (size_t)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > \fBshared_ptr\fP< \fB_UnboundedArray\fP< \fB_Yp\fP > > \fBmake_shared\fP (size_t, \fBconst\fP \fBremove_extent_t\fP< \fB_Yp\fP > &)"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > \fBshared_ptr\fP< \fB_NotUnboundedArray\fP< \fB_Yp\fP > > \fBmake_shared_for_overwrite\fP ()"
.br
.ti -1c
.RI "template<typename \fB_Yp\fP > \fBshared_ptr\fP< \fB_UnboundedArray\fP< \fB_Yp\fP > > \fBmake_shared_for_overwrite\fP (size_t)"
.br
.ti -1c
.RI "\fBclass\fP \fBweak_ptr< _Tp >\fP"
.br
.in -1c
.SS "Related Symbols"
(Note that these are not member symbols\&.) 
.in +1c
.ti -1c
.RI "template<typename \fB_Del\fP , typename _Tp > \fB_Del\fP * \fBget_deleter\fP (\fBconst\fP \fBshared_ptr\fP< _Tp > &__p) noexcept"
.br
.RI "20\&.7\&.2\&.2\&.10 shared_ptr get_deleter "
.ti -1c
.RI "template<typename \fB_Ch\fP , typename \fB_Tr\fP , typename _Tp , _Lock_policy _Lp> \fBstd::basic_ostream\fP< \fB_Ch\fP, \fB_Tr\fP > & \fBoperator<<\fP (\fBstd::basic_ostream\fP< \fB_Ch\fP, \fB_Tr\fP > &\fB__os\fP, \fBconst\fP __shared_ptr< _Tp, \fB_Lp\fP > &__p)"
.br
.RI "Write the stored pointer to an ostream\&. "
.in -1c
.PP
.RI "\fB\fP"
.br

.in +1c
.in +1c
.ti -1c
.RI "template<typename _Tp , typename _Up > bool \fBoperator==\fP (\fBconst\fP \fBshared_ptr\fP< _Tp > &__a, \fBconst\fP \fBshared_ptr\fP< _Up > &__b) noexcept"
.br
.ti -1c
.RI "template<typename _Tp > bool \fBoperator==\fP (\fBconst\fP \fBshared_ptr\fP< _Tp > &__a, nullptr_t) noexcept"
.br
.RI "shared_ptr comparison with nullptr "
.ti -1c
.RI "template<typename _Tp > \fBvoid\fP \fBswap\fP (\fBshared_ptr\fP< _Tp > &__a, \fBshared_ptr\fP< _Tp > &__b) noexcept"
.br
.RI "Swap overload for shared_ptr\&. "
.ti -1c
.RI "template<typename _Tp , typename _Up > \fBshared_ptr\fP< _Tp > \fBstatic_pointer_cast\fP (\fBconst\fP \fBshared_ptr\fP< _Up > &__r) noexcept"
.br
.RI "Convert type of \fRshared_ptr\fP, via \fRstatic_cast\fP "
.ti -1c
.RI "template<typename _Tp , typename _Up > \fBshared_ptr\fP< _Tp > \fBconst_pointer_cast\fP (\fBconst\fP \fBshared_ptr\fP< _Up > &__r) noexcept"
.br
.RI "Convert type of \fRshared_ptr\fP, via \fRconst_cast\fP "
.ti -1c
.RI "template<typename _Tp , typename _Up > \fBshared_ptr\fP< _Tp > \fBdynamic_pointer_cast\fP (\fBconst\fP \fBshared_ptr\fP< _Up > &__r) noexcept"
.br
.RI "Convert type of \fRshared_ptr\fP, via \fRdynamic_cast\fP "
.ti -1c
.RI "template<typename _Tp , typename _Up > \fBshared_ptr\fP< _Tp > \fBreinterpret_pointer_cast\fP (\fBconst\fP \fBshared_ptr\fP< _Up > &__r) noexcept"
.br
.RI "Convert type of \fRshared_ptr\fP, via \fRreinterpret_cast\fP "
.ti -1c
.RI "template<typename _Tp , typename _Up > \fBshared_ptr\fP< _Tp > \fBstatic_pointer_cast\fP (\fBshared_ptr\fP< _Up > &&__r) noexcept"
.br
.RI "Convert type of \fRshared_ptr\fP rvalue, via \fRstatic_cast\fP "
.ti -1c
.RI "template<typename _Tp , typename _Up > \fBshared_ptr\fP< _Tp > \fBconst_pointer_cast\fP (\fBshared_ptr\fP< _Up > &&__r) noexcept"
.br
.RI "Convert type of \fRshared_ptr\fP rvalue, via \fRconst_cast\fP "
.ti -1c
.RI "template<typename _Tp , typename _Up > \fBshared_ptr\fP< _Tp > \fBdynamic_pointer_cast\fP (\fBshared_ptr\fP< _Up > &&__r) noexcept"
.br
.RI "Convert type of \fRshared_ptr\fP rvalue, via \fRdynamic_cast\fP "
.ti -1c
.RI "template<typename _Tp , typename _Up > \fBshared_ptr\fP< _Tp > \fBreinterpret_pointer_cast\fP (\fBshared_ptr\fP< _Up > &&__r) noexcept"
.br
.RI "Convert type of \fRshared_ptr\fP rvalue, via \fRreinterpret_cast\fP "
.in -1c
.in -1c
.PP
.RI "\fB\fP"
.br

.in +1c
.in +1c
.ti -1c
.RI "template<typename _Tp , typename _Alloc , typename\&.\&.\&. _Args> \fBshared_ptr\fP< \fB_NonArray\fP< _Tp > > \fBallocate_shared\fP (\fBconst\fP _Alloc &__a, \fB_Args\fP &&\&.\&.\&. \fB__args\fP)"
.br
.RI "Create an object that is owned by a shared_ptr\&. "
.ti -1c
.RI "template<typename _Tp , typename\&.\&.\&. _Args> \fBshared_ptr\fP< \fB_NonArray\fP< _Tp > > \fBmake_shared\fP (\fB_Args\fP &&\&.\&.\&. \fB__args\fP)"
.br
.RI "Create an object that is owned by a shared_ptr\&. "
.ti -1c
.RI "template<typename _Tp , typename _Alloc > \fBshared_ptr\fP< \fB_UnboundedArray\fP< _Tp > > \fBallocate_shared\fP (\fBconst\fP _Alloc &__a, size_t __n)"
.br
.RI "Create an object that is owned by a shared_ptr\&. "
.ti -1c
.RI "template<typename _Tp , typename _Alloc > \fBshared_ptr\fP< \fB_BoundedArray\fP< _Tp > > \fBallocate_shared\fP (\fBconst\fP _Alloc &__a)"
.br
.RI "Create an object that is owned by a shared_ptr\&. "
.in -1c
.in -1c
.SH "Detailed Description"
.PP 

.SS "template<typename _Tp>
.br
class std::shared_ptr< _Tp >"A smart pointer with reference-counted copy semantics\&. 


.PP
\fBSince\fP
.RS 4
C++11
.RE
.PP
A \fRshared_ptr\fP object is either empty or \fIowns\fP a pointer passed to the constructor\&. Copies of a \fRshared_ptr\fP share ownership of the same pointer\&. When the last \fRshared_ptr\fP that owns the pointer is destroyed or reset, the owned pointer is freed (either by \fRdelete\fP or by invoking a custom deleter that was passed to the constructor)\&.
.PP
A \fRshared_ptr\fP also stores another pointer, which is usually (but not always) the same pointer as it owns\&. The stored pointer can be retrieved by calling the \fRget()\fP member function\&.
.PP
The equality and relational operators for \fRshared_ptr\fP only compare the stored pointer returned by \fRget()\fP, not the owned pointer\&. To test whether two \fRshared_ptr\fP objects share ownership of the same pointer see \fRstd::shared_ptr::owner_before\fP and \fRstd::owner_less\fP\&. 
.SH "Member Typedef Documentation"
.PP 
.SS "template<typename _Tp > \fBusing\fP \fBstd::shared_ptr\fP< _Tp >::element_type"

.PP
The type pointed to by the stored pointer, remove_extent_t<_Tp> 
.SS "template<typename _Tp > \fBusing\fP \fBstd::shared_ptr\fP< _Tp >::weak_type"

.PP
The corresponding weak_ptr type for this shared_ptr\&. 
.PP
\fBSince\fP
.RS 4
C++17 
.RE
.PP

.SH "Constructor & Destructor Documentation"
.PP 
.SS "template<typename _Tp > \fBconstexpr\fP \fBstd::shared_ptr\fP< _Tp >::shared_ptr ()\fR [inline]\fP, \fR [constexpr]\fP, \fR [noexcept]\fP"

.PP
Construct an empty shared_ptr\&. 
.PP
\fBPostcondition\fP
.RS 4
use_count()==0 && get()==0 
.RE
.PP

.SS "template<typename _Tp > \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fBconst\fP \fBshared_ptr\fP< _Tp > &)\fR [default]\fP, \fR [noexcept]\fP"

.PP
Copy constructor\&. 
.SS "template<typename _Tp > template<typename \fB_Yp\fP , typename  = _Constructible<_Yp*>> \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fB_Yp\fP * __p)\fR [inline]\fP, \fR [explicit]\fP"

.PP
Construct a shared_ptr that owns the pointer \fI__p\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A pointer that is convertible to element_type*\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fRdelete\fP \fI__p\fP is called\&. 
.RE
.PP

.SS "template<typename _Tp > template<typename \fB_Yp\fP , typename \fB_Deleter\fP , typename  = _Constructible<_Yp*, _Deleter>> \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fB_Yp\fP * __p, \fB_Deleter\fP __d)\fR [inline]\fP"

.PP
Construct a shared_ptr that owns the pointer \fI__p\fP and the deleter \fI__d\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A pointer\&. 
.br
\fI__d\fP A deleter\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fI__d(__p)\fP is called\&.
.RE
.PP
Requirements: _Deleter's copy constructor and destructor must not throw
.PP
__shared_ptr will release __p by calling __d(__p) 
.SS "template<typename _Tp > template<typename \fB_Deleter\fP > \fBstd::shared_ptr\fP< _Tp >::shared_ptr (nullptr_t __p, \fB_Deleter\fP __d)\fR [inline]\fP"

.PP
Construct a shared_ptr that owns a null pointer and the deleter \fI__d\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A null pointer constant\&. 
.br
\fI__d\fP A deleter\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fI__d(__p)\fP is called\&.
.RE
.PP
Requirements: _Deleter's copy constructor and destructor must not throw
.PP
The last owner will call __d(__p) 
.SS "template<typename _Tp > template<typename \fB_Yp\fP , typename \fB_Deleter\fP , typename _Alloc , typename  = _Constructible<_Yp*, _Deleter, _Alloc>> \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fB_Yp\fP * __p, \fB_Deleter\fP __d, _Alloc __a)\fR [inline]\fP"

.PP
Construct a shared_ptr that owns the pointer \fI__p\fP and the deleter \fI__d\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A pointer\&. 
.br
\fI__d\fP A deleter\&. 
.br
\fI__a\fP An allocator\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fI__d(__p)\fP is called\&.
.RE
.PP
Requirements: _Deleter's copy constructor and destructor must not throw _Alloc's copy constructor and destructor must not throw\&.
.PP
__shared_ptr will release __p by calling __d(__p) 
.SS "template<typename _Tp > template<typename \fB_Deleter\fP , typename _Alloc > \fBstd::shared_ptr\fP< _Tp >::shared_ptr (nullptr_t __p, \fB_Deleter\fP __d, _Alloc __a)\fR [inline]\fP"

.PP
Construct a shared_ptr that owns a null pointer and the deleter \fI__d\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__p\fP A null pointer constant\&. 
.br
\fI__d\fP A deleter\&. 
.br
\fI__a\fP An allocator\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == 1 && get() == __p 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIstd::bad_alloc,in\fP which case \fI__d(__p)\fP is called\&.
.RE
.PP
Requirements: _Deleter's copy constructor and destructor must not throw _Alloc's copy constructor and destructor must not throw\&.
.PP
The last owner will call __d(__p) 
.SS "template<typename _Tp > template<typename \fB_Yp\fP > \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fBconst\fP \fBshared_ptr\fP< \fB_Yp\fP > & __r, \fBelement_type\fP * __p)\fR [inline]\fP, \fR [noexcept]\fP"

.PP
Constructs a \fRshared_ptr\fP instance that stores \fR__p\fP and shares ownership with \fR__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A \fRshared_ptr\fP\&. 
.br
\fI__p\fP A pointer that will remain valid while \fR*__r\fP is valid\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
\fRget() == __p && use_count() == __r\&.use_count()\fP
.RE
.PP
This can be used to construct a \fRshared_ptr\fP to a sub-object of an object managed by an existing \fRshared_ptr\fP\&. The complete object will remain valid while any \fRshared_ptr\fP owns it, even if they don't store a pointer to the complete object\&.
.PP
.PP
.nf
shared_ptr<pair<int,int>> pii(new pair<int,int>());
shared_ptr<int> pi(pii, &pii\->first);
assert(pii\&.use_count() == 2);
.fi
.PP
 
.SS "template<typename _Tp > template<typename \fB_Yp\fP > \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fBshared_ptr\fP< \fB_Yp\fP > && __r, \fBelement_type\fP * __p)\fR [inline]\fP, \fR [noexcept]\fP"

.PP
Constructs a \fRshared_ptr\fP instance that stores \fR__p\fP and shares ownership with \fR__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A \fRshared_ptr\fP\&. 
.br
\fI__p\fP A pointer that will remain valid while \fR*__r\fP is valid\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
\fRget() == __p && !__r\&.use_count() && !__r\&.get()\fP 
.RE
.PP
\fBSince\fP
.RS 4
C++17
.RE
.PP
This can be used to construct a \fRshared_ptr\fP to a sub-object of an object managed by an existing \fRshared_ptr\fP\&. The complete object will remain valid while any \fRshared_ptr\fP owns it, even if they don't store a pointer to the complete object\&.
.PP
.PP
.nf
shared_ptr<pair<int,int>> pii(new pair<int,int>());
shared_ptr<int> pi1(pii, &pii\->first);
assert(pii\&.use_count() == 2);
shared_ptr<int> pi2(std::move(pii), &pii\->second);
assert(pii\&.use_count() == 0);
.fi
.PP
 
.SS "template<typename _Tp > template<typename \fB_Yp\fP , typename  = _Constructible<const shared_ptr<_Yp>&>> \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fBconst\fP \fBshared_ptr\fP< \fB_Yp\fP > & __r)\fR [inline]\fP, \fR [noexcept]\fP"

.PP
If \fI__r\fP is empty, constructs an empty shared_ptr; otherwise construct a shared_ptr that shares ownership with \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A shared_ptr\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
get() == __r\&.get() && use_count() == __r\&.use_count() 
.RE
.PP

.SS "template<typename _Tp > \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fBshared_ptr\fP< _Tp > && __r)\fR [inline]\fP, \fR [noexcept]\fP"

.PP
Move-constructs a shared_ptr instance from \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A shared_ptr rvalue\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
*this contains the old value of \fI__r\fP, \fI__r\fP is empty\&. 
.RE
.PP

.SS "template<typename _Tp > template<typename \fB_Yp\fP , typename  = _Constructible<shared_ptr<_Yp>>> \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fBshared_ptr\fP< \fB_Yp\fP > && __r)\fR [inline]\fP, \fR [noexcept]\fP"

.PP
Move-constructs a shared_ptr instance from \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A shared_ptr rvalue\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
*this contains the old value of \fI__r\fP, \fI__r\fP is empty\&. 
.RE
.PP

.SS "template<typename _Tp > template<typename \fB_Yp\fP , typename  = _Constructible<const weak_ptr<_Yp>&>> \fBstd::shared_ptr\fP< _Tp >::shared_ptr (\fBconst\fP \fBweak_ptr\fP< \fB_Yp\fP > & __r)\fR [inline]\fP, \fR [explicit]\fP"

.PP
Constructs a shared_ptr that shares ownership with \fI__r\fP and stores a copy of the pointer stored in \fI__r\fP\&. 
.PP
\fBParameters\fP
.RS 4
\fI__r\fP A weak_ptr\&. 
.RE
.PP
\fBPostcondition\fP
.RS 4
use_count() == __r\&.use_count() 
.RE
.PP
\fBExceptions\fP
.RS 4
\fIbad_weak_ptr\fP when __r\&.expired(), in which case the constructor has no effect\&. 
.RE
.PP

.SS "template<typename _Tp > \fBconstexpr\fP \fBstd::shared_ptr\fP< _Tp >::shared_ptr (nullptr_t)\fR [inline]\fP, \fR [constexpr]\fP, \fR [noexcept]\fP"

.PP
Construct an empty shared_ptr\&. 
.PP
\fBPostcondition\fP
.RS 4
use_count() == 0 && get() == nullptr 
.RE
.PP

.SH "Member Function Documentation"
.PP 
.SS "template<typename _Tp , _Lock_policy _Lp> \fBelement_type\fP * std::__shared_ptr< _Tp, \fB_Lp\fP >::get () const\fR [inline]\fP, \fR [noexcept]\fP, \fR [inherited]\fP"

.PP
Return the stored pointer\&. 
.SS "template<typename _Tp , _Lock_policy _Lp> std::__shared_ptr< _Tp, \fB_Lp\fP >::operator bool () const\fR [inline]\fP, \fR [explicit]\fP, \fR [noexcept]\fP, \fR [inherited]\fP"

.PP
Return true if the stored pointer is not null\&. 
.SS "template<typename _Tp , _Lock_policy _Lp> template<typename \fB_Tp1\fP > bool std::__shared_ptr< _Tp, \fB_Lp\fP >::owner_before (__shared_ptr< \fB_Tp1\fP, \fB_Lp\fP > \fBconst\fP & __rhs) const\fR [inline]\fP, \fR [noexcept]\fP, \fR [inherited]\fP"

.PP
Define an ordering based on ownership\&. This function defines a strict weak ordering between two shared_ptr or weak_ptr objects, such that one object is less than the other unless they share ownership of the same pointer, or are both empty\&. 
.SS "template<typename _Tp , _Lock_policy _Lp> template<typename \fB_Tp1\fP > bool std::__shared_ptr< _Tp, \fB_Lp\fP >::owner_before (__weak_ptr< \fB_Tp1\fP, \fB_Lp\fP > \fBconst\fP & __rhs) const\fR [inline]\fP, \fR [noexcept]\fP, \fR [inherited]\fP"

.PP
Define an ordering based on ownership\&. This function defines a strict weak ordering between two shared_ptr or weak_ptr objects, such that one object is less than the other unless they share ownership of the same pointer, or are both empty\&. 
.SS "template<typename _Tp , _Lock_policy _Lp> \fBvoid\fP std::__shared_ptr< _Tp, \fB_Lp\fP >::swap (__shared_ptr< _Tp, \fB_Lp\fP > & __other)\fR [inline]\fP, \fR [noexcept]\fP, \fR [inherited]\fP"

.PP
Exchange both the owned pointer and the stored pointer\&. 
.SS "template<typename _Tp , _Lock_policy _Lp> bool std::__shared_ptr< _Tp, \fB_Lp\fP >::unique () const\fR [inline]\fP, \fR [noexcept]\fP, \fR [inherited]\fP"

.PP
Return true if use_count() == 1\&. 
.SS "template<typename _Tp , _Lock_policy _Lp> long std::__shared_ptr< _Tp, \fB_Lp\fP >::use_count () const\fR [inline]\fP, \fR [noexcept]\fP, \fR [inherited]\fP"

.PP
If *this owns a pointer, return the number of owners, otherwise zero\&. 

.SH "Author"
.PP 
Generated automatically by Doxygen for libstdc++ from the source code\&.